New safety tool at O'Hare

FAA says system cuts collision risk

The all-too-real risk of planes colliding at O'Hare International Airport has been reduced with the deployment of new runway safety equipment, the Federal Aviation Administration said Thursday.

The radar-based airfield monitoring system began operating this month, almost two years ahead of the FAA's original schedule because of concerns over a series of recent near-collisions on O'Hare's crisscrossing runways. The Illinois congressional delegation pushed the FAA to hasten the technology upgrade at O'Hare, the nation's second-busiest airport.

The new system is designed to give air-traffic controllers an earlier warning about potential collisions involving planes taxiing on the airfield and aircraft coming in for landings or departing. The name of the system is the Airport Surface Detection Equipment Model X.

Chicago aviation officials said they are happy the system came to the airport sooner rather than later.

"While the installation of this technology is transparent to the public, it further enhances travel safety for our customers," said Karen Pride, spokeswoman for the Chicago Department of Aviation.

O'Hare is the 11th U.S. airport to operate the system, which feeds images to a computer display in the airport tower. Icons representing planes are shown moving across the airfield. Approaching planes up to 5 miles away that are preparing to land are also depicted, giving controllers a view of all corners of the airport and the nearby airspace.

The sophisticated airfield surveillance system is scheduled to go online at Midway Airport in 2008, said FAA spokeswoman Elizabeth Isham Cory. The FAA has so far selected 35 of the nation's more than 420 commercial airports to receive ASDE-X.

One of the most serious O'Hare incidents, which are categorized as runway incursions, happened July 23, 2006, when a United Airlines jet cleared for takeoff barely missed colliding at a runway intersection with an Atlas Air cargo plane that had landed moments earlier.

The pilots of the United plane, carrying 120 passengers and five crew members, pulled their Boeing 737 into the sky early to avoid an accident, clearing the tail section of the Boeing 747 cargo plane by only 35 feet, an investigation found. The FAA attributed the runway incursion to errors by an air-traffic controller in the O'Hare tower.

Two other O'Hare runway incursions occurred in March 2006, including one in which two planes came within 100 feet of crashing during takeoff on intersecting runways.

The aircraft movement monitoring system that ASDE-X is replacing at O'Hare often was shut down for repairs or turned off because it gave too many false alarms, especially during rain when visibility is reduced and an enhanced picture of aircraft moving on the ground is essential, controllers said.

In addition, the old system, called the Airport Movement Area Safety System, provides as little as an 8-second alert before a potential accident, not enough time for controllers to react and radio avoidance-maneuver instructions to pilots, officials said.

That system was in standby mode at the time of the July 2006 near-collision because it had been emitting false alerts on runway incursions, according to an investigation by the National Transportation Safety Board. Investigators also determined that an AMASS warning would have been too late to prevent a collision in that incident.

Aviation safety experts and pilot unions welcome the addition of ASDE-X at airports. But they say the FAA should move forward more quickly with a cockpit-based runway-incursion alert system so that pilots can directly view what is happening on the airfield and receive the earliest possible warning about potential conflicts.

The FAA is testing several systems.

Eight runway incursions occurred at O'Hare in 2006, including three in which the risk of an accident was moderate to high, the FAA said.

Five runway incursions have occurred at O'Hare this year, according to the FAA. All were in the lowest classification in terms of severity, or likelihood of an accident, Cory said.

O'Hare controllers said the new system's introduction was long overdue.

"This is the best piece of equipment I've seen since 1970. There is no downside," said Joseph Bellino, union president at O'Hare tower for the National Air Traffic Controllers Association.

Runway incursions represent one of the biggest risks to safety at U.S. airports, according to the National Transportation Safety Board. The NTSB said the most severe types of runway incursions are happening with "alarming frequency" at U.S. airports.

The ASDE-X system at O'Hare is undergoing a month of testing and training of controllers, Cory said. The system is expected to be officially commissioned for use about Aug. 30, she said.